Unable to read PDF files from Kiwix-serve

[Popolechien]

It used to be that a user trying to access a PDF file from their mobile phone via Kiwix-serve (either directly from library.kiwix.org or from the hotspot) would be able to read them directly and without problem.

But now trying to check https://library.kiwix.org/viewer#maitre_lucas_completer_les_mots_fr_2023-05/files/compl%C3%A9ter%20les%20mots%205.pdf from my mobile leads to this:

Phone is Nothing phone 2 running Android 14 and Google Chrome 122.0.6261.119

[kelson42]

library.kiwix.org link works fine for me on my android. @rgaudin Do you see anything weird at http response level? Might that be that the problem is that the browser can simply nor handle properly the PDF (within the iframe)?

[rgaudin]

I can reproduce on Chrome/Android but not on Firefox/Android

[rgaudin]

Refused to frame '' because it violates the following Content Security Policy directive: "frame-src 'self'".
viewer.js?cacheid=5fc4badf:282 Uncaught DOMException: Failed to read a named property 'href' from 'Location': Blocked a frame with origin "https://library.kiwix.org" from accessing a cross-origin frame.
    at handle_content_url_change (https://library.kiwix.org/skin/viewer.js?cacheid=5fc4badf:282:62)
    at on_content_load (https://library.kiwix.org/skin/viewer.js?cacheid=5fc4badf:393:5)
    at HTMLIFrameElement.onload (https://library.kiwix.org/viewer#maitre_lucas_completer_les_mots_fr_2023-05/home:77:32)
viewer.js?cacheid=5fc4badf:208 Uncaught TypeError: Cannot read properties of null (reading 'documentElement')
    at updateToolbarVisibilityState (viewer.js?cacheid=5fc4badf:208:24)

[veloman-yunkan]

It turns out that since v85 and until very recently (though as an experimental feature) Chrome on Android doesn't support displaying PDF's inline.

@kelson42:

library.kiwix.org link works fine for me on my android.

This seems to suggest that (as of the time of your comment) your chrome's version was pre-85

@rgaudin:

I can reproduce [the bug] on Chrome/Android but not on Firefox/Android

My guess is that you were using a more recent version of Chrome.

Having checked that my phone runs Chrome 132 I tried to enable the experimental support for native PDF preview but when it didn't work I was surprised to find out that I am still running Android 10 (below the minimal version 12 on which that functionality is supported). Will have to use a different device for debugging/testing.

[veloman-yunkan]

Well, Chrome 132 on Android 14 with "Open PDF Inline" flags enabled also doesn't display PDFs (but proposes to download them) when PDF links are clicked on https://maitrelucas.fr/fiche/completer-les-mots-cp-ce1/.

Even if we manage to display PDFs inline in Chrome (132+) on Android (12+), there will be configurations where it won't work. Best we can do is to download the file (instead of attempting to load it in the iframe). I will provide a quickfix for that workaround.